A thermoplastic fluoroelastomer has excellent heat resistance, abrasion resistance, chemical resistance, solvent resistance, oil resistance, etc. and is formed in the form of a tube, sheet, film and other forms (eg. O-ring, sealing materials, etc.) or applied on various substrates such as electric wires or cables, building materials, clamping devices, and so forth.
The thermoplastic fluoroelastomer is, as is understood from its nomenclature, plasticized when heated and easily molded. Since its plasticizing temperature is, however, usually higher than 200.degree. C., special equipment is required for plasticizing it. In addition, special equipment for cross-linking is also required. When the thermoplastic fluoroelastomer is molded on the spot, it is necessary to formulate a composition which is molded and preferably hardened at room temperature. The thermoplastic fluoroelastomer is easily dissolved or dispersed in a medium to afford a composition hardenable at room temperature. However, an article having a larger thickness, such as an O-ring cannot be molded from a solution or dispersion.
As a result of extensive study, it has now been found that formulation of a liquid fluoroelastomer and, optionally, a cross-linking agent, in thermoplastic, fluoroelastomer, affords a composition which is easily ejection molded and hardened at room temperature.